\begin{tikzpicture}
	\tkzDefPoints{-2/0/A, 2/0/B, 0/1.5/C, 0/-1.5/D}
	\tkzInterLL(A,B)(C,D)   \tkzGetPoint{M}

	\tkzDrawSegments[xianduan={below=0pt}](A,B)
	\tkzDrawSegments(C,D)
	\tkzMarkRightAngle(B,M,C)
	\tkzLabelPoints[below](A,B)
	\tkzLabelPoints[right](C,D)
	\tkzLabelPoints[above left](M)
\end{tikzpicture}

